Heretofore known are a variety of gas-barrier, multi-layer plastics film laminates useful as packaging materials for enveloping processed meat or like food. Among them are seamless tubes of gas-barrier, preferably heat-shrinkable, multi-layer plastics film laminate having a layer of olefin resin for contact with processed meat or the like to be enclosed therein. However, such seamless tubes of multi-layer plastics film laminate with the innermost polyolefin resin layer have drawbacks. Since the olefin resin layer has a poor property of closely contacting food, particularly ham, sausage or like processed meat, a gap is formed between the processed meat and the packaging material on heat-shrink packaging or after a time interval, followed by occurrence of the so-called release of gravy, water or the like from the processed meat into the gap. In that case, bacteria easily proliferate and the proliferation of bacteria renders the processed meat or the like less preservable.
To cope with the problem, various methods have been conventionally carried out which include, for example, applying to the olefin resin layer a substance capable of closely contacting processed meat or the like, forming the innermost layer capable of closely contacting meat, or treating the innermost layer by corona discharge to improve the degree of close contact with processed meat or the like. However, these methods have both advantages and disadvantages and thus remain to be improved.